Despite representing less than 3% of all trips made by UK residents, journeys exceeding 50 miles one way account for 70% of all passenger travel-related carbon emissions, according to new research published in the journal Nature Energy. The disparity is even starker in international travel, which, while comprising only 0.4% of total trips, contributes to 55% of emissions.
The study suggests that focusing on reducing emissions from long-distance travel could be more effective than current efforts aimed at local and commuter journeys. Although domestic car travel for both long and short distances has declined slightly over the past 25 years, international air travel has surged, driven by an increase in leisure trips and visits to friends and family.
Using a newly developed metric called “emission reduction sensitivity,” the researchers identified which types of travel changes could most effectively reduce carbon emissions from passenger travel with minimal impact on the number of people or trips affected.
The findings show that shifting all car journeys under eight miles to walking or cycling could reduce carbon emissions by 9.3%. However, this change would require altering 55% of all journeys, resulting in an emission reduction sensitivity value of just 0.17, the lowest in the study.
In contrast, moving all flights under 1,000 miles to rail would achieve a 5.6% reduction in emissions, affecting only 0.17% of journeys. This change has a significantly higher sensitivity value of 33.2. Limiting individuals to one return flight abroad per year would yield a sensitivity value of 158.3, as it would impact a relatively small number of journeys.
The researchers emphasize that these suggestions are intended to raise awareness and encourage reassessment of the impact of long-distance travel rather than serve as concrete policy proposals. They hope the findings will prompt policymakers to re-evaluate the focus of efforts to mitigate the environmental impact of travel.
The data for the research was sourced from the Department for Transport’s National Travel Survey and the International Passenger Survey conducted by the Office for National Statistics.
The study also aims to provide the public with insights into how altering their travel behavior can significantly impact carbon emissions.